Confused about Frustrum and Vertex Shader

---- solved ----

Hi all,

i allready work with shaders for some time, but today i am totally confused about a strange beavior.
I just strted a new opengl project and implemented a simple shader pair...
I was getting no visible result so i started testing around ..

In my new setup Project i only get visible output when i set 'gl_Position.z' between -1 and 1

I donīt understand why, cause as i use my onw Programm( shader pair ) and my own matrix fpr perspective
the opengl frustrum or any other global state should not have any effect on the visible range ( near / far clipping plane ).

Do in need to set a Frustum when i use shader and my own matrix ?

Can anyone tell me what i am doing wrong ??
What is my mistake - have i missunderstood something ??

thanx a lot !!
uwi

(edit) sorry i just spent 5 min away from the pc and now its all obvious to me.... question solved !